The techniques for the large-scale higher organism cell culturing used today are divided into two large groups: those in which the cells are suspended in a stirred nutrient medium or those in which the cells adhere to a solid support bathed with the nutrient medium. Cells which adhere to a solid support are generally referred to as “anchorage dependent” cells. The nutrient medium is generally a liquid comprising a basal nutrient mixture and can also contain a biological extract e.g. serum derived from mammalian blood, in the absence of which the cells would no longer be viable and they would lose their ability to proliferate. In the past years, cell culture media have been developed, in which cells can be grown and maintained in the absence of serum. These media are generally called serum-free media.
For anchorage dependent cells one of the most frequently used methods today consists of using so-called roller bottles as the culture container, which bottles are usually arranged on roller racks which provide the bottles the corresponding rotation. In these roller bottles, the cells adhere to the inner wall of the bottle such that the continuous rotation thereof keeps the cell layer (the thickness of the cell layer is often equivalent to one of them, and in this case it is referred to as “single-layer”) in contact with the nutrient medium. When the cells are cultured in said media, they remain viable for a finite period until one or more nutrients of the medium is used up. Once this time has passed it is necessary to empty and refresh or replace the content of the nutrient medium inside the roller bottles, without entraining or damaging the aforementioned single-layer, which means that emptying movements must be extremely gentle and careful.
Based on the description provided above, emptying these bottles today, an operation, which in addition must be carried out very frequently with large-scale cultures, is carried out by hand or by means of very expensive and complex robots. Overturning the bottles by hand causes problems with tendonitis, discomfort in the hands and shoulders and the so-called carpal tunnel syndrome in the operators responsible for carrying out this operation with a high daily frequency. When the bottles are overturned using robots there is a problem due to the lack of gentleness in said movement, as well as the existence of vibrations, which results in the single-layer becoming detached or damaged on many occasions.
The present invention aims to solve the limits set forth above.